The background of the present disclosure is hereinafter introduced with the discussion of techniques relating to its context. However, even when this discussion refers to documents, acts, artifacts and the like, it does not suggest or represent that the discussed techniques are part of the prior art or are common general knowledge in the field relevant to the present disclosure.
Containers of impervious material (for example, glass) are commonly used to store liquids in a number of applications. Particularly, in medical applications the containers store medical liquids to be administered to patients; for example, in hospital environments these containers are commonplace for storing contrast agents that are to be injected into the patients (such as by an automated injection system during scan examinations thereof).
Most containers have a mouth (i.e., an opening) for loading and delivering the liquid; a typical example is a bottle, i.e., a rigid container having a larger body with a neck ending with the mouth. Each container of this type is provided with a closure, which closes the container to avoid losing the liquid and to protect the liquid from environment contamination (before its use).
A widespread type of closure is based on a membrane that seals the mouth of the container. In this case, a spike (for example, a needle) is commonly used to pierce the membrane for extracting the liquid from the container through it (with the container that remains substantially closed even when the spike is removed after the administration of the liquid). However, any accidental contacts with the spike may contaminate it and then the liquid when the spike is inserted into the container, with a consequent final possible contamination of the patient. Moreover, the spike is quite hazardous and it may cause injuries to a corresponding operator, with the risk of transmitting diseases as well.
Alternatively, the closure may be provided with an internal spike (which is not accessible from the outside). In this case, when a delivery device is coupled with the closure (for example, by screwing a luer lock fitting), the delivery device pushes the spike that pierces the membrane analogously to the previous technique.
In any case, the piercing of the membrane by the spike (either internally or externally to the closure) may cause the detachment of particles of the membrane and their falling within the container, with the risk of contamination of the liquid stored in the container.
Closures that do not require any spike for delivering the liquid (i.e., of the spike-less type) have also been proposed. For example, a closure of this type may be provided with a valve member that closes a delivery port of the liquid. When the delivery device is coupled with the closure of the container, the delivery device pushes the valve member inwards the container, thereby opening the delivery port that allows the liquid to flow from the container to the delivery device. The delivery port of the closure may also be sealed by a frangible element, which is broken by the valve member when it opens the delivery port.
Moreover, the closure may be provided with an elastic element associated with the valve member. According to this technique, the delivery device pushes the valve member to open the delivery port in opposition to the elastic element; therefore, when the delivery device is removed (after the administration of the liquid) the elastic element moves back the valve member so as to close the delivery port again.
In addition, as mentioned in WO-A-98/34582, the closure may have an air release valve to allow air to flow into the container as the liquid is delivered. As described in US-A-2011/0168292, the closure may also have one or more air-release openings, or vents, which are provided with an umbrella valve, with a long tube and a short tube or with a self-sealing valve; the air-release openings are sealed by a microhole covering, which is a semi-permeable membrane that allows air to enter or to exit but it does not permit the passage of liquids.
However, none of the closures known in the art is completely satisfactory under several points of view. For example, improvements would be desirable with respect to structure, assembling, usage and safety of the closures.